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BIODEGRADABLE ALIPHATIC/AROMATIC COPOLYESTERS BASED ON TEREPHTHALIC ACID AND POLY(L-LACTIC ACID):SYNTHESIS,CHARACTERIZATION AND HYDROLYTIC DEGRADATION
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作者 方征平 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第3期405-415,共11页
Biodegradable aliphatic/aromatic copolyesters, poly(butylene terephthalate-co-lactate) (PBTL) were prepared via direct melt polycondensation of terephthalic acid (TPA), 1,4-butanediol (BDO) and poly(L-lactic ... Biodegradable aliphatic/aromatic copolyesters, poly(butylene terephthalate-co-lactate) (PBTL) were prepared via direct melt polycondensation of terephthalic acid (TPA), 1,4-butanediol (BDO) and poly(L-lactic acid) oligomer (OLLA). The effects of polymerization time and temperature, as well as aliphatic/aromatic moiety ratio on the physical and thermal properties were investigated. The largest molecular weight of the copolyesters was up to 64100 with molecular weight distribution index of 2.09 when the polycondensation was carried out at 230℃ for 6 h. DSC, XRD, DMA and TGA analysis clearly indicated that the degree of crystallinity, glass-transition temperature, melting point, decomposition temperature, tensile strength, elongation and Young's modulus were influenced by the ratio between TPA and OLLA in the final copolyesters. Hydrolytic degradation results demonstrated that the incorporation of biodegradable lactate moieties into the aromatic polyester could efficiently improve hydrolytic degradability of the copolymer even though it still had many aromatic units in the main chains. 展开更多
关键词 aliphatic/aromatic copolyesters Direct melt polycondensation BIODEGRADABLE
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Interface-directed porous aromatic framework nanoflakes for ultrafast quasi-homogeneous photocatalytic aerobic oxidation in air
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作者 Hengtao Lei Yuhui Zhai +6 位作者 Jian Song Xiaojun Zhao Ayesha Javaid Geng Tan Yuyang Tian Qinhe Pan Guangshan Zhu 《Science China Chemistry》 2026年第2期900-906,共7页
The development of efficient photocatalysts for crucial organic transformation,such as aerobic oxidation,remains challenging.Although powdered porous materials offer abundant accessible active sites,their application ... The development of efficient photocatalysts for crucial organic transformation,such as aerobic oxidation,remains challenging.Although powdered porous materials offer abundant accessible active sites,their application in liquid-phase catalysis is often limited by insufficient light absorption and inevitable charge recombination,which are inherent drawbacks of conventional heterogeneous catalysts.Here,through rational design and nanoscale-engineering of porous aromatic frameworks(PAFs)comprising porphyrin and porous organic cage,a quasi-homogeneous porous photocatalyst with high catalytic activity and controllable dimension was developed.The interface-directed growth in oil-in-water emulsion shaped the morphology of photoactive PAFs from powders to nanoflakes,which facilitated the light absorbance and catalyst-substrate interaction.Compared with PAF powders,PAF nanoflakes exhibited superior photocatalytic activity for aerobic oxidation.For mustard gas simulant(2-chloroethyl ethyl sulfide,CEES),PAF nanoflakes exhibited ultrafast detoxification rates in room air with a half-life(t_(1/2))as fast as 26s,which even exceeded other catalysts in pure oxygen.It also completely catalyzed the aerobic oxidation of thioether within 15 min,which is almost the fastest rate among any reported organic photocatalysts.Furthermore,the efficient catalytic performance under mild conditions caused by improved light enrichment,surface charge transfer and carrier lifetime was elucidated. 展开更多
关键词 porous aromatic framework morphology control nanoflake photocatalysis aerobic oxidation
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Planting nitrogen-rich motif into porous aromatic frameworks to boost redox potential and multi-ion storage for wide-temperature sodium-organic batteries
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作者 Mimi Zhang Linqi Cheng +3 位作者 Zhaoli Liu Fengchao Cui Fang Luo Heng-Guo Wang 《Science China Chemistry》 2026年第2期979-985,共7页
Redox-active porous aromatic frameworks(PAFs)have emerged as hopeful candidates for sodium-ion batteries(SIBs)in view of their porous structures,chemical stability and tunable architectures.Herein,we successfully synt... Redox-active porous aromatic frameworks(PAFs)have emerged as hopeful candidates for sodium-ion batteries(SIBs)in view of their porous structures,chemical stability and tunable architectures.Herein,we successfully synthesized two redox-active PAFs(PAF-305 and PAF-306)with different nitrogen-containing motifs,and demonstrated their application as cathode materials for SIBs.Density functional theory(DFT)calculations reveal that nitrogen-rich PAF-305 exhibits a lower lowest unoccupied molecular orbital(LUMO)energy level(-3.35 eV)and a narrower energy gap(E_(g))(2.40 eV)compared with nitrogen-poor PAF-306.As expected,PAF-305 displays outstanding electrochemical performance,comprising a high reversible capacity of 145.2 mAh g^(-1)at 0.05 A g^(-1)and satisfactory cycling stability with 92% capacity retention over 1000 cycles at 0.2 A g^(-1).Remarkably,PAF-305 maintains robust electrochemical properties across a wide temperature range(-20℃ to 50℃).Through a combination of experimental characterizations and theoretical calculations,the sodium-ion storage mechanism of PAF-305 is elucidated.This study not only provides a promising strategy for exploring other redox-active organic units in the design of novel PAFs,but also expands the potential applications of PAFs in energy storage systems. 展开更多
关键词 porous aromatic framework nitrogen-rich motif multi-ion storage wide temperature sodium-organic batteries
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Membrane materials in the pervaporation separation of aromatic/aliphatic hydrocarbon mixtures—A review 被引量:13
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作者 Hong-Xia Liu Naixin Wang +2 位作者 Cui Zhao Shulan Ji Jian-Rong Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第1期1-16,共16页
The separation of aromatic/aliphatic hydrocarbon mixtures is a significant process in chemical industry, but challenged in some cases. Compared with conventional separation technologies, pervaporation is quite promisi... The separation of aromatic/aliphatic hydrocarbon mixtures is a significant process in chemical industry, but challenged in some cases. Compared with conventional separation technologies, pervaporation is quite promising in terms of its economical, energy-saving, and eco-friendly advantages. However, this technique has not been used in industry for separating aromatic/aliphatic mixtures yet. One of the main reasons is that the separation performance of existed pervaporation membranes is unsatisfactory. Membrane material is an important factor that affects the separation performance. This review provides an overview on the advances in studying membrane materials for the pervaporation separation of aromatic/aliphatic mixtures over the past decade. Explored pristine polymers and their hybrid materials(as hybrid membranes) are summarized to highlight their nature and separation performance. We anticipate that this review could provide some guidance in the development of new materials for the aromatic/aliphatic pervaporation separation. 展开更多
关键词 aromatic/aliphatic hydrocarbon mixtures Membrane materials Pervaporation separation
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Hyperbranched polymer hollow-fiber-composite membranes for pervaporation separation of aromatic/aliphatic hydrocarbon mixtures 被引量:1
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作者 Tong Liu Hao Sun +5 位作者 Xiangqiong Wang Jie Li Zhanquan Zhang Pei Wu Naixin Wang Quanfu An 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期13-22,共10页
The separation of aromatic/aliphatic hydrocarbon mixtures is crucial in the petrochemical industry.Pervaporation is regarded as a promising approach for the separation of aromatic compounds from alkanes. Developing me... The separation of aromatic/aliphatic hydrocarbon mixtures is crucial in the petrochemical industry.Pervaporation is regarded as a promising approach for the separation of aromatic compounds from alkanes. Developing membrane materials with efficient separation performance is still the main task since the membrane should provide chemical stability, high permeation flux, and selectivity. In this study, the hyperbranched polymer(HBP) was deposited on the outer surface of a polyvinylidene fluoride(PVDF)hollow-fiber ultrafiltration membrane by a facile dip-coating method. The dip-coating rate, HBP concentration, and thermal cross-linking temperature were regulated to optimize the membrane structure.The obtained HBP/PVDF hollow-fiber-composite membrane had a good separation performance for aromatic/aliphatic hydrocarbon mixtures. For the 50%/50%(mass) toluene/n-heptane mixture, the permeation flux of optimized composite membranes could reach 1766 g·m^(-2)·h^(-1), with a separation factor of 4.1 at 60℃. Therefore, the HBP/PVDF hollow-fiber-composite membrane has great application prospects in the pervaporation separation of aromatic/aliphatic hydrocarbon mixtures. 展开更多
关键词 aromatic/aliphatic hydrocarbons Hyperbranched polymer PERVAPORATION Hollow fiber membrane DIP-COATING
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Preparation and characterization of biodegradable aliphatic-aromatic copolyesters/nano-SiO_2 hybrids via in situ melt polycondensation 被引量:2
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作者 Yan Zhang Bing Tao Wang +2 位作者 Zheng Hong Guo Jie Chen Zheng Ping Fang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第11期1348-1352,共5页
In situ melt polycondensation was proposed to prepare biodegradable aliphatic-aromatic copolyesters/nano-SiO2 hybrids based on terephthalic acid (TPA), poly(L-lactic acid) oligomer (OLLA), 1,4-butanediol (BDO)... In situ melt polycondensation was proposed to prepare biodegradable aliphatic-aromatic copolyesters/nano-SiO2 hybrids based on terephthalic acid (TPA), poly(L-lactic acid) oligomer (OLLA), 1,4-butanediol (BDO) and nano-SiO2. TEM and FT-IR characterizations confirmed that TPA, OLLA and BDO copolymerized to obtain biodegradable copolyesters, poly(butylene terepbthalate-co-lactate) (PBTL), and the abundant hydroxyl groups on the surface of nano-SiO2 provided potential sites for in situ grafting with the simultaneous resulted PBTL. The nano-SiO2 particles were chemically wrapped with PBTL to form PBTL/nano- SiO2 hybrids. Due to the good dispersion and interfacial adhesion of nano-SiO2 particles with the copolyester matrix, the tensile strength and the Young's modulus increased from 5.4 and 5.6 MPa for neat PBTL to 16 and 390 MPa for PBTL/nano-SiO2 hybrids with 5 wt.% nano-SiO2, respectively. The mechanical properties of PBTL/nano-SiO2 hybrids were substantially improved. 展开更多
关键词 Biodegradable aliphatic-aromatic copolyesters PBTL/nano-SiO2 hybrids In situ melt polycondensation
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Highly selective extraction of aromatics from aliphatics by using metal chloride-based ionic liquids
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作者 Hui Yu Xiaojia Wu +4 位作者 Chuanqi Geng Xinyu Li Chencan Du Zhiyong Zhou Zhongqi Ren 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期222-229,共8页
The separation of aromatics from aliphatics is essential for achieving maximum exploitation of oil resources in the petrochemical industry.In this study,a series of metal chloride-based ionic liquids were prepared and... The separation of aromatics from aliphatics is essential for achieving maximum exploitation of oil resources in the petrochemical industry.In this study,a series of metal chloride-based ionic liquids were prepared and their performances in the separation of 1,2,3,4-tetrahydronaphthalene(tetralin)/dodecane and tetralin/decalin systems were studied.Among these ionic liquids,1-ethyl-3-methylimidazolium tetrachloroferrate([EMIM][FeCl_(4)])with the highest selectivity was used as the extractant.Density functional theory calculations showed that[EMIM][FeCl_(4)]interacted more strongly with tetralin than with dodecane and decalin.Energy decomposition analysis of[EMIM][FeCl_(4)]-tetralin indicated that electrostatics and dispersion played essential roles,and induction cannot be neglected.The van der Waals forces was a main effect in[EMIM][FeCl_(4)]-tetralin by independent gradient model analysis.The tetralin distribution coefficient and selectivity were 0.8 and 110,respectively,with 10%(mol)tetralin in the initial tetralin/dodecane system,and 0.67 and 19.5,respectively,with 10%(mol)tetralin in the initial tetralin/decalin system.The selectivity increased with decreasing alkyl chain length of the extractant.The influence of the extraction temperature,extractant dosage,and initial concentrations of the system components on the separation performance were studied.Recycling experiments showed that the regenerated[EMIM][FeCl_(4)]could be used repeatedly. 展开更多
关键词 Ionic liquid aromatic hydrocarbon aliphatic hydrocarbon Extraction
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Study on Structure and Crystallinity of A New Biodegradable Aliphatic-Aromatic Copolyester
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作者 Wang Xiaohui Shi Jun +2 位作者 Chen Ying Fu Zhifeng Shi Yan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2011年第4期64-69,共6页
A series of biodegradable aliphatic-aromatic copolyesters, poly(butylene terephthalate-co-butylene adipate-co- ethylene terephthalate-co-ethylene adipate) (PBATE), were synthesized from terephthalic acid (PTA), adipic... A series of biodegradable aliphatic-aromatic copolyesters, poly(butylene terephthalate-co-butylene adipate-co- ethylene terephthalate-co-ethylene adipate) (PBATE), were synthesized from terephthalic acid (PTA), adipic acid (AA), 1,4-butanediol (BG) and ethylene glycol (EG) through direct esterification and polycondensation. The sequence structure and crystallinity of the copolyester were investigated by 1H NMR spectroscopy and the wide-angle X-ray diffractometry (WAXD). The analytical results showed that the PBATE copolyester was a random copolymer and the composition of PBATE copolyester was almost consistent with the feed molar ratios. The crystal structure of PBATE copolyester belonged to the triclinic crystalline system; The variation in melting point of the synthesized PBATE copolyester agreed well with the estimation obtained by the Flory equation and was applicable to the random copolymer. 展开更多
关键词 biodegradable polyester sequence structure CRYSTALLINITY aliphatic aromatic
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Organosoluble Aliphatic-Aromatic Poly(ether-amide)s Based on Pyridine Moiety in the Main Chain: Synthesis, Characterization and Thermal Studies
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作者 Mohsen Hajibeygi Meisam Shabanian 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2014年第6期758-767,共10页
A series organosoluble and heterocyclic poly(ether-amide)s (PEA)s were synthesized from a new diamine containing pyridine moiety and four aliphatic-aromatic dicarboxylic acids by direct polycondensation reactions.... A series organosoluble and heterocyclic poly(ether-amide)s (PEA)s were synthesized from a new diamine containing pyridine moiety and four aliphatic-aromatic dicarboxylic acids by direct polycondensation reactions. Dicarboxilic acids 4a-4d containing ether groups were synthesized in two step reactions. At first, dialdehydes 3a-3d were synthesized from four dibromo alkanes la-ld and 4-hydroxybenzaldehyde 2, then dicarboxilic acids 4a-4d were synthesized from dialdehydes 3a-3d and malonic acid in a solvent free reaction. On the other hand, the new diamine 8 containing pyridine ring was synthesized in two step reactions. The structures of synthesized monomers and polymers were proven by FTIR, NMR spectroscopy and elemental analysis. Also all of the above polymers were fully characterized by inherent viscosity, solubility tests, gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The resulted PEAs have shown good inherent viscosities, solubility and thermal properties. 展开更多
关键词 Poly(ether-amide) ORGANOSOLUBLE aliphatic-aromatic Polycondensation Malonic acid.
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Decoding the mechanism of P450-catalyzed aromatic hydroxylation:Uncovering the arene oxide pathway and insights into the regioselectivity 被引量:2
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作者 Qun Huang Xuan Zhang +8 位作者 Guangwu Sun Rui-ying Qiu Lan Luo Cuizhen Wang Longwei Gao Bing Gao Bo Chen Binju Wang Jian-bo Wang 《Chinese Journal of Catalysis》 2025年第3期420-430,共11页
P450 enzymes-catalyzed aromatic hydroxylation plays an important role in detoxification,biosynthesis,and potential carcinogenic effect of aromatic compounds.Though it has been explored for decades,the actual process o... P450 enzymes-catalyzed aromatic hydroxylation plays an important role in detoxification,biosynthesis,and potential carcinogenic effect of aromatic compounds.Though it has been explored for decades,the actual process of aromatic hydroxylation and mechanism of regioselectivity catalyzed by cytochrome P450 monooxygenases remained ambiguous.Here,we have resolved these issues.With a stable chiral organofluorine probe,and especially with X-ray data of two isolated arene oxides derivatives,we demonstrate that an arene oxide pathway is definitely involved in P450-catalyzed aromatic hydroxylation.By the capture,isolation,identification and reactivity exploration of the arene 1,2-oxide and arene 2,3-oxide intermediates,together with advanced QM calculations,the mechanism of how two intermediates go to the same product has been elucidated.In addition to the model substrate,we also confirmed that an arene oxide intermediate is involved in the P450-catalyzed hydroxylation pathway of a natural product derivative methyl cinnamate,which indicates that this intermediate appears to be universal in P450-catalyzed aromatic hydroxylation.Our work not only provides the most direct evidence for the arene oxide pathway and new insights into the regioselectivity involved in P450-catalyzed aromatic hydroxylation,but also supplies a new synthetic approach to achieve the dearomatization of aromatic compounds. 展开更多
关键词 aromatic hydroxylation Cytochrome P450 Arene oxide Regioselectivity DEaromatIZATION
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Effects of photo-oxidation and transition metals on the formation of reactive oxygen species from aromatic compounds using spectroscopic method 被引量:1
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作者 Xiaoyu Hu Juanjuan Qin +5 位作者 Yuanyuan Qin Tianyi Zhao Yuxuan Cao Qinghe Cai Lijia Zhang Yang Zhang 《Journal of Environmental Sciences》 2025年第5期1-11,共11页
Particulate matter(PM)can cause adverse health effects by overproducing reactive oxygen species(ROS).Although the ability of PM to induce ROS generation depends on its composi-tion and environmental factors.This study... Particulate matter(PM)can cause adverse health effects by overproducing reactive oxygen species(ROS).Although the ability of PM to induce ROS generation depends on its composi-tion and environmental factors.This study explores how photo-oxidation affects ROS gen-eration from aromatic compounds(ACs,including catechol(CAT),phthalic acid(PA),and 4,4-oxydibenzoic acid(4,4-OBA))and their mixtures with transition metals(TMs,includ-ing Fe(II),Mn(II),and Cu(II))using Fourier-transform infrared(FTIR)and Ultraviolet-visible spectroscopy(UV-Vis).Results showed that photo-oxidation facilitated ROS generation from ACs.CAT-Fe(II)/Cu(II)showed synergistic effects,but 4,4-OBA-Fe(II)/Cu(II)showed antag-onistic effects.ACs-Mn(II)and PA-Fe(II)/Cu(II)exhibited synergistic effects first and then showed antagonistic effects.The different interactions were due to complexation between ACs and TMs.The photo-oxidized ACs-TMs significantly enhanced ROS generation com-pared with ACs-TMs.The study suggested the photo-oxidation mechanism involved that the transfer ofπ-electrons from the ground to an excited state in benzene rings and func-tional groups,leading to the breakage and formation of chemical bonds or easierπ-electron transfer from ACs to TMs.The former could generate ROS directly or produce polymers that promoted ROS generation,while the latter promoted ROS generation by transferringπ-electrons to dissolved oxygen quickly.Our study revealed that both interactions among components and photo-oxidation significantly influenced ROS generation.Future studies should integrate broader atmospheric factors and PM components to fully assess oxidative potential and health impacts. 展开更多
关键词 Reactive oxygen species aromatic compounds Transitional metals PHOTO-OXIDATION
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Associations of polycyclic aromatic hydrocarbons exposure with serum uric acid and hyperuricemia in US adults:The role of systemic inflammation 被引量:1
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作者 Yang Liu Xuejie Ding +7 位作者 Linling Yu Da Shi Ruyi Liang Wei Liu Xuezan Huang Xiuyu Cao Min Zhou Weihong Chen 《Journal of Environmental Sciences》 2025年第4期412-421,共10页
The associations of polycyclic aromatic hydrocarbon(PAH)exposure with serum uric acid(SUA)or hyperuricemia have been rarely assessed.We aimed to investigate the relationships between urinary PAH metabolites and SUA or... The associations of polycyclic aromatic hydrocarbon(PAH)exposure with serum uric acid(SUA)or hyperuricemia have been rarely assessed.We aimed to investigate the relationships between urinary PAH metabolites and SUA or hyperuricemia among US adults and to explore the mediating role of systemic inflammation in the associations.A total of 10,307 US adults were conducted to assess the associations of seven urinary hydroxy–PAH with SUA and hyperuricemia and evaluate the role of C-reactive protein(CRP),a biomarker of systemic inflammation,in such associations.Results showed that each 1-unit increase in ln-transformed 2-hydroxynaphthalene(2-OHNa),1-hydroxyphenanthrene(1-OHPh),2&3-hydroxyphenanthrene(2&3-OHPh)and total hydroxyphenanthrene(OHPh)was associated with a 1.68(95%confidence interval(CI):0.19 to 3.17),2.46(0.78 to 4.13),3.34(1.59 to 5.09),and 2.99(1.23 to 4.75)μmol/L increase in SUA,and a 8%(odds ratio(OR):1.08,1.02 to 1.15),9%(OR:1.09,1.02 to 1.18),13%(OR:1.13,1.05 to 1.22),and 12%(OR:1.12,95%CI:1.03,1.21)increase in hyperuricemia,respectively.Co-exposure of seven PAHs was positively associated with SUA and hyperuricemia,with 2&3-OHPh showing the highest weight(components weights:0.83 and 0.78,respectively).The CRP mediated 11.47%and 10.44%of the associations ofΣOHPh and 2&3-OHPh with SUA and mediated 8.60%and 8.62%in associations ofΣOHPh and 2&3-OHPh with hyperuricemia,respectively.In conclusion,internal levels of PAH metabolites were associated with elevated SUA levels and the increased risk of hyperuricemia among US adults,and CRP played a mediating role in the associations. 展开更多
关键词 Polycyclic aromatic hydrocarbon Serum uric acid HYPERURICEMIA C-reactive protein General population
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Local aromatic ring cleaves the global aromatic ring in hexaphyrin(2.1.2.1.2.1)
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作者 Xiaojuan Lv Yuting Dong +8 位作者 Hongliang Huang Dariusz W.Szczepanik Naoki Aratani Takahisa Ikeue Feng Chen Tao Zhang Fengxian Qiu Toshiharu Teranishi Songlin Xue 《Chinese Chemical Letters》 2025年第7期308-311,共4页
Novel benzo-bridged hexaphyrin(2.1.2.1.2.1)and its copper complex were synthesized.Single-crystal structures showed typical figure-of-eight Huckel topologies.NMR,NICS,HOMA,ACID,and EDDB analysis supported their non-ar... Novel benzo-bridged hexaphyrin(2.1.2.1.2.1)and its copper complex were synthesized.Single-crystal structures showed typical figure-of-eight Huckel topologies.NMR,NICS,HOMA,ACID,and EDDB analysis supported their non-aromatic properties owning to the strong local aromatic benzo rings cutting the global aromatic ring of the benzo-bridged figure-of-eight hexaphyrin(2.1.2.1.2.1).The redox properties and degenerate HOMOs and LUMOs levels indicate multielectron donating and accepting abilities. 展开更多
关键词 Local aromaticity Global aromaticity Hexaphyrin(2.1.2.1.2.1) CLEAVAGE Multielectron DFT calculation
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Installation of Multiple Chiral Centers in Aliphatic Polyesters Backbone Enables Unexpected Crystallinity via Asymmetric Catalytic Copolymerization
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作者 Zheng-Fei Liu Bai-Hao Ren +4 位作者 Yi-Shu Fu Jun Yang Yong-Qiang Teng Ye Liu Xiao-Bing Lu 《Chinese Journal of Polymer Science》 2025年第6期946-951,I0008,共7页
The asymmetric alternating copolymerization of meso-epoxide and cyclic anhydrides provides an efficient access to enantiopure polyesters.Contrary to the extensive investigation of the stereochemistry resulting from ep... The asymmetric alternating copolymerization of meso-epoxide and cyclic anhydrides provides an efficient access to enantiopure polyesters.Contrary to the extensive investigation of the stereochemistry resulting from epoxide building block,the chirality from anhydride and the configurational match with epoxide remain elusive.Herein,we discover that the bimetallic chromium catalysts have led to an obvious enhancement in terms of reactivity and enantioselectivity for the asymmetric copolymerization of meso-epoxide with various non-symmetric chiral anhydrides.Up to 97%ee was obtained during the asymmetric copolymerization of cyclohexene oxide(CHO)with(R)-methylsuccinic anhydride(R-MSA),and three-or four-carbon chiral centers were simultaneously installed in the aliphatic polyester backbone.In particular,the different combinations of stereochemistry in epoxide and anhydride building blocks considerably affect the thermal properties and crystalline behaviors of the resulting polyesters.This study uncovers an interesting method for regulating polymer crystallinity via matching the chirality of different monomers. 展开更多
关键词 CHIRALITY Bimetallic catalyst Asymmetric copolymerization aliphatic polyester
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Effects of polycyclic aromatic hydrocarbon enrichment on microbial community structure in polar sediments
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作者 LYU Zhe CHU Jiajun +2 位作者 LI Dong ZHANG Xiao-Hua SHI Xiaochong 《Advances in Polar Science》 2025年第4期320-330,共11页
Understanding microbial responses to polycyclic aromatic hydrocarbon(PAH)pollution is crucial for assessing the current status of PAH contamination in polar regions.In this study,intertidal and marine sediments were e... Understanding microbial responses to polycyclic aromatic hydrocarbon(PAH)pollution is crucial for assessing the current status of PAH contamination in polar regions.In this study,intertidal and marine sediments were enriched with a mixture of PAHs(naphthalene,phenanthrene,fluorene,pyrene,and fluoranthene).Isolation of culturable bacteria,high-throughput sequencing,and functional prediction were combined to systematically analyze bacterial structural and predicted functional responses to PAH exposure.High-throughput sequencing results showed that the relative abundance of Proteobacteria was significantly increased after enrichment,and Pseudomonas and Acinetobacter were identified as dominant genera under PAH exposure.These findings were consistent with the 19 potential PAH-degrading strains(mainly Pseudomonas)that were successfully isolated from enrichment cultures.Distinct bacterial taxa between enriched marine and intertidal sediments indicated the existence of distinct PAH-degrading groups.PICRUSt2-based functional predictions suggested higher predicted abundances of PAH-degradation pathways in polar sediments,likely through the preferential degradation of parent PAH compounds in response to elevated concentrations.This study provides valuable data on microbial responses to PAH pollution in polar regions and offers new insights for evaluating ecological hazards induced by PAHs. 展开更多
关键词 polycyclic aromatic hydrocarbon microbial community ARCTIC ANTARCTIC
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Diverse Subtypes of Cardiovascular Disease Risk Evaluated by Novel PREVENT Associated with Different Polycyclic Aromatic Hydrocarbon Metabolites
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作者 Ye Xin Yucheng Sun +7 位作者 Lin Chen Fengtao Cui Yingge Duan Hanyun Wang Li Chen Tian Chen Piye Niu Junxiang Ma 《Biomedical and Environmental Sciences》 2025年第10期1217-1229,共13页
Objective To investigate the association of various polycyclic aromatic hydrocarbon(PAH)metabolites with diverse subtypes of cardiovascular disease(CVD)risk.Methods A novel predicting risk of cardiovascular disease EV... Objective To investigate the association of various polycyclic aromatic hydrocarbon(PAH)metabolites with diverse subtypes of cardiovascular disease(CVD)risk.Methods A novel predicting risk of cardiovascular disease EVENTs PREVENT equation was used to estimate the 10-year diverse subtypes of CVD risk,and their associations with PAH metabolites were analyzed using multiple logistic regression models,the weighted quantile sum(WQS)model,the quantile g-computation(qgcomp)model,and a stratified analysis of subgroups.Results For this study,six thousand seven hundred and forty-five participants were selected,and significant positive associations were observed between PAHs,naphthalene(NAP),and fluorene(FLU),and the risks of total CVD,atherosclerotic cardiovascular disease(ASCVD),and heart failure(HF).NAP and FLU were the primary contributors to the effects of PAH mixtures,and their associations with total CVD,ASCVD,and HF risk were significant in younger participants(30≤age<50 years);however,the associations of phenanthrene(PHEN)with ASCVD,HF,coronary heart disease(CHD),and stroke were dominant in aging participants(age≥50 years).Notably,pyrene(PYR)was negatively associated with the risk of ASCVD,HF,CHD,and stroke.Similarly,negative associations of PYR with the four CVD subtypes were noticeable in aging participants.Conclusion Different PAHs metabolites had different impacts on each CVD subtype among different age groups.Notably,the protective effects of PYR on ASCVD,HF,CHD,and stroke were noticeable in aging individuals. 展开更多
关键词 Cardiovascular disease PREVENT equation Polycyclic aromatic hydrocarbon NHANES
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The Intrinsic Link between Optical Properties and Toxicity of Extractable Organic Matter in Combustion Particles:Mediated by Polycyclic Aromatic Compounds
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作者 Chuxin Yao Jiao Tang +8 位作者 Guangcai Zhong Huimin Ma Yangzhi Mo Xiaofei Geng Xin Yi Qianyu Zhang Jun Li Shizhen Zhao Gan Zhang 《Environment & Health》 2025年第7期768-776,共9页
Organic compounds are important contributors to the optical properties and health effects of combustion-derived particles.However,the connection between optical properties and toxicity of combustion particles remains ... Organic compounds are important contributors to the optical properties and health effects of combustion-derived particles.However,the connection between optical properties and toxicity of combustion particles remains a matter of little concern.In this study,combustion particles were collected from 11 primary sources,including biomass burning,coal combustion,and vehicle exhaust.The extractable organic matter(EOM)in bituminous coal combustion particles shows the highest light-absorption,fluorescence properties,and toxicity among samples.Parallel factor(PARAFAC)analysis combined excitation−emission matrix(EEM)spectroscopy resolved 4 types of basic chromophore components in EOM.Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)analysis further resolved∼800 molecules,predominantly aromatics(84%±4.6%),which showed positive correlations with the light-absorption,fluorescence properties and toxicity of EOM(p<0.05).Aromatics are inferred to be the intrinsic link between the optical properties and toxicity of EOM in combustion particles.Additionally,the benzene poly(carboxylic acid)s(BPCAs)method,which could identify and quantify fused benzene rings in EOM,further indicates the high condensation degree of aromatics is closely correlated with the lightabsorption,fluorescence properties of EOM.However,the toxicity of EOM may depend on the bay or fjord region of aromatics.These findings provide valuable insights into the light-absorption,fluorescence properties and toxicity of EOM in combustion particles. 展开更多
关键词 Combustion particles FT-ICR MS Optical properties Toxicity aromaticS BPCAs
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Bilayered Dion-Jacobson lead-iodine hybrid perovskite with aromatic spacer for broadband photodetection
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作者 Dongying Fu Lin Pan +1 位作者 Yanli Ma Yue Zhang 《Chinese Chemical Letters》 2025年第2期558-561,共4页
Dion-Jacobson (DJ) phase hybrid perovskites have been proven to improve the photovoltaic performance of the devices due to its unique structure.At present,some DJ hybrid perovskites have been reported and used for pho... Dion-Jacobson (DJ) phase hybrid perovskites have been proven to improve the photovoltaic performance of the devices due to its unique structure.At present,some DJ hybrid perovskites have been reported and used for photodetection filed,but most of them are based on lead-bromide systems,which is not conducive to construct broadband photodetection devices due to the limitation of intrinsic absorption.Herein,we constructed a bilayered DJ hybrid perovskite (3AMPY)(EA)Pb_(2)I_(7)(3AMPY^(2+)is 3-(aminomethyl)pyridinium,EA^(+)is ethylammonium) using an aromatic spacer,which exhibit large current on/off ratios of 10~4under 520 and 637 nm illumination.In particular,the single crystal device based on (3AMPY)(EA)Pb_(2)I_(7)shows a distinguished detectivity of 7.4×10^(12)Jones and a high responsivity of 0.89A/W under 637 nm illumination.Such finding not only enriches the quantities of DJ hybrid perovskites,but also provides useful assistance for constructing high-performance optoelectronic device in the future. 展开更多
关键词 Dion-Jacobson Hybrid perovskite aromatic spacer Two-dimensional Broadband photodetection
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Complex-mediated nucleophilic aromatic substitution with aryl nitriles to realize intramolecular flapping-restricted D-A AIEgens for bioimaging
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作者 Feng Liu Junkai Liu +10 位作者 Junyi Gong Runfeng Lin Siyuan Qiu Zicheng Liu Chongyang Li Miao Meng Shijie Li Mei Tu Jacky WYLam Guangle Niu Ming Chen 《Smart Molecules》 2025年第2期72-82,共11页
Donor-acceptor(D-A)compounds are particularly important in optoelectronic and biological applications.However,they are normally synthesized in the presence of transition metal catalysts.Herein,we report a metal-free m... Donor-acceptor(D-A)compounds are particularly important in optoelectronic and biological applications.However,they are normally synthesized in the presence of transition metal catalysts.Herein,we report a metal-free method by a complexmediated nucleophilic aromatic substitution of aryl nitriles with amines.The method can lead to rich D-A type aggregation-induced emission luminogens(AIEgens)with tunable properties.They emit from deep-blue to yellow-green and possess high photoluminescence quantum yields up to 70.5%in the aggregate state.Interestingly,the suppression of intramolecular flapping is proved to play an indispensable role in the AIE behavior,which is different from the mechanism met in other AIEgens.Moreover,the biocompatible AIEgens possess specific staining of lipid droplets in HeLa cells and the superiority of identifying fatty liver over traditional Oil Red O staining is exhibited. 展开更多
关键词 aggregation-induced emission BIOIMAGING donor-acceptor structure nucleophilic aromatic substitution
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Removal mechanisms of polycyclic aromatic hydrocarbons in biochar and its effects on plant growth
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作者 Canxu Yao Bing Wang +2 位作者 Masud Hassan Huajie Xu Xiangui Wang 《Journal of Environmental Sciences》 2025年第12期309-323,共15页
Polycyclic aromatic hydrocarbons(PAHs)could be produced during the preparation of biochar,which may pose potential risks to the environment and human health.Existing research mainly focuses on the removal efficiency o... Polycyclic aromatic hydrocarbons(PAHs)could be produced during the preparation of biochar,which may pose potential risks to the environment and human health.Existing research mainly focuses on the removal efficiency of PAHs in biochar using different methods.Still,there are few reports on the removal mechanism of PAHs and the impact of treated biochar on plant growth.This study prepared biochar by pyrolysis of sewage sludge,pig manure,and distillers grains at 300,500,and 600℃,respectively.The prepared biochar was subjected to thermal treatment,water washing treatment,and hydrothermal treatment to investigate the removal mechanism of PAHs in biochar and evaluate its effect on plant growth.The results showed that the removal rates of PAHs in biochar by hydrothermal treatment,thermal treatment,and water washing were 36.79%-86.09%,80.00%-89.90%,and 19.15%-72.40%,respectively.Compared with thermal treatment and water washing treatments,the hydrothermal treatment is more effective.The removal rate of PAHs in sludge biochar with a pyrolysis temperature of 300℃ by hydrothermal treatment reached 86.09%under 80℃ for 2 h.The removal mechanisms of PAHs include weakening hydrophobic interaction and thermal desorption.The germination results indicate that treated biochar reduces malondialdehyde content in mung bean seedlings and increases superoxide dismutase,peroxidase,and catalase activities.Sludge biochar after hydrothermal treatment is more conducive to the growth of mung beans than pristine biochar.This study provides an effective pathway for the safe utilization of biochar. 展开更多
关键词 BIOCHAR Polycyclic aromatic hydrocarbons Removal mechanisms Hydrothermal treatment Plant growth
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